Revision 7103559f49b46b3287973045f741c0679e3e9e44 authored by Sagar Vemuri on 21 June 2018, 18:02:49 UTC, committed by Facebook Github Bot on 21 June 2018, 18:13:08 UTC
Summary: This PR extends the improvements in #3282 to also work when using Direct IO. We see **4.5X performance improvement** in seekrandom benchmark doing long range scans, when using direct reads, on flash. **Description:** This change improves the performance of iterators doing long range scans (e.g. big/full index or table scans in MyRocks) by using readahead and prefetching additional data on each disk IO, and storing in a local buffer. This prefetching is automatically enabled on noticing more than 2 IOs for the same table file during iteration. The readahead size starts with 8KB and is exponentially increased on each additional sequential IO, up to a max of 256 KB. This helps in cutting down the number of IOs needed to complete the range scan. **Implementation Details:** - Used `FilePrefetchBuffer` as the underlying buffer to store the readahead data. `FilePrefetchBuffer` can now take file_reader, readahead_size and max_readahead_size as input to the constructor, and automatically do readahead. - `FilePrefetchBuffer::TryReadFromCache` can now call `FilePrefetchBuffer::Prefetch` if readahead is enabled. - `AlignedBuffer` (which is the underlying store for `FilePrefetchBuffer`) now takes a few additional args in `AlignedBuffer::AllocateNewBuffer` to allow copying data from the old buffer. - Made sure not to re-read partial chunks of data that were already available in the buffer, from device again. - Fixed a couple of cases where `AlignedBuffer::cursize_` was not being properly kept up-to-date. **Constraints:** - Similar to #3282, this gets currently enabled only when ReadOptions.readahead_size = 0 (which is the default value). - Since the prefetched data is stored in a temporary buffer allocated on heap, this could increase the memory usage if you have many iterators doing long range scans simultaneously. - Enabled only for user reads, and disabled for compactions. Compaction reads are controlled by the options `use_direct_io_for_flush_and_compaction` and `compaction_readahead_size`, and the current feature takes precautions not to mess with them. **Benchmarks:** I used the same benchmark as used in #3282. Data fill: ``` TEST_TMPDIR=/data/users/$USER/benchmarks/iter ./db_bench -benchmarks=fillrandom -num=1000000000 -compression_type="none" -level_compaction_dynamic_level_bytes ``` Do a long range scan: Seekrandom with large number of nexts ``` TEST_TMPDIR=/data/users/$USER/benchmarks/iter ./db_bench -benchmarks=seekrandom -use_direct_reads -duration=60 -num=1000000000 -use_existing_db -seek_nexts=10000 -statistics -histogram ``` ``` Before: seekrandom : 37939.906 micros/op 26 ops/sec; 29.2 MB/s (1636 of 1999 found) With this change: seekrandom : 8527.720 micros/op 117 ops/sec; 129.7 MB/s (6530 of 7999 found) ``` ~4.5X perf improvement. Taken on an average of 3 runs. Closes https://github.com/facebook/rocksdb/pull/3884 Differential Revision: D8082143 Pulled By: sagar0 fbshipit-source-id: 4d7a8561cbac03478663713df4d31ad2620253bb
1 parent 524c6e6
src.mk
# These are the sources from which librocksdb.a is built:
LIB_SOURCES = \
cache/clock_cache.cc \
cache/lru_cache.cc \
cache/sharded_cache.cc \
db/builder.cc \
db/c.cc \
db/column_family.cc \
db/compacted_db_impl.cc \
db/compaction.cc \
db/compaction_iterator.cc \
db/compaction_job.cc \
db/compaction_picker.cc \
db/compaction_picker_universal.cc \
db/convenience.cc \
db/db_filesnapshot.cc \
db/db_impl.cc \
db/db_impl_compaction_flush.cc \
db/db_impl_debug.cc \
db/db_impl_experimental.cc \
db/db_impl_files.cc \
db/db_impl_open.cc \
db/db_impl_readonly.cc \
db/db_impl_write.cc \
db/db_info_dumper.cc \
db/db_iter.cc \
db/dbformat.cc \
db/event_helpers.cc \
db/experimental.cc \
db/external_sst_file_ingestion_job.cc \
db/file_indexer.cc \
db/flush_job.cc \
db/flush_scheduler.cc \
db/forward_iterator.cc \
db/internal_stats.cc \
db/logs_with_prep_tracker.cc \
db/log_reader.cc \
db/log_writer.cc \
db/malloc_stats.cc \
db/managed_iterator.cc \
db/memtable.cc \
db/memtable_list.cc \
db/merge_helper.cc \
db/merge_operator.cc \
db/range_del_aggregator.cc \
db/repair.cc \
db/snapshot_impl.cc \
db/table_cache.cc \
db/table_properties_collector.cc \
db/transaction_log_impl.cc \
db/version_builder.cc \
db/version_edit.cc \
db/version_set.cc \
db/wal_manager.cc \
db/write_batch.cc \
db/write_batch_base.cc \
db/write_controller.cc \
db/write_thread.cc \
env/env.cc \
env/env_chroot.cc \
env/env_encryption.cc \
env/env_hdfs.cc \
env/env_posix.cc \
env/io_posix.cc \
env/mock_env.cc \
memtable/alloc_tracker.cc \
memtable/hash_cuckoo_rep.cc \
memtable/hash_linklist_rep.cc \
memtable/hash_skiplist_rep.cc \
memtable/skiplistrep.cc \
memtable/vectorrep.cc \
memtable/write_buffer_manager.cc \
monitoring/histogram.cc \
monitoring/histogram_windowing.cc \
monitoring/instrumented_mutex.cc \
monitoring/iostats_context.cc \
monitoring/perf_context.cc \
monitoring/perf_level.cc \
monitoring/statistics.cc \
monitoring/thread_status_impl.cc \
monitoring/thread_status_updater.cc \
monitoring/thread_status_updater_debug.cc \
monitoring/thread_status_util.cc \
monitoring/thread_status_util_debug.cc \
options/cf_options.cc \
options/db_options.cc \
options/options.cc \
options/options_helper.cc \
options/options_parser.cc \
options/options_sanity_check.cc \
port/port_posix.cc \
port/stack_trace.cc \
table/adaptive_table_factory.cc \
table/block.cc \
table/block_based_filter_block.cc \
table/block_based_table_builder.cc \
table/block_based_table_factory.cc \
table/block_based_table_reader.cc \
table/block_builder.cc \
table/block_fetcher.cc \
table/block_prefix_index.cc \
table/bloom_block.cc \
table/cuckoo_table_builder.cc \
table/cuckoo_table_factory.cc \
table/cuckoo_table_reader.cc \
table/flush_block_policy.cc \
table/format.cc \
table/full_filter_block.cc \
table/get_context.cc \
table/index_builder.cc \
table/iterator.cc \
table/merging_iterator.cc \
table/meta_blocks.cc \
table/partitioned_filter_block.cc \
table/persistent_cache_helper.cc \
table/plain_table_builder.cc \
table/plain_table_factory.cc \
table/plain_table_index.cc \
table/plain_table_key_coding.cc \
table/plain_table_reader.cc \
table/sst_file_writer.cc \
table/table_properties.cc \
table/two_level_iterator.cc \
tools/dump/db_dump_tool.cc \
util/arena.cc \
util/auto_roll_logger.cc \
util/bloom.cc \
util/build_version.cc \
util/coding.cc \
util/compaction_job_stats_impl.cc \
util/comparator.cc \
util/compression_context_cache.cc \
util/concurrent_arena.cc \
util/crc32c.cc \
util/delete_scheduler.cc \
util/dynamic_bloom.cc \
util/event_logger.cc \
util/file_reader_writer.cc \
util/file_util.cc \
util/filename.cc \
util/filter_policy.cc \
util/hash.cc \
util/log_buffer.cc \
util/murmurhash.cc \
util/random.cc \
util/rate_limiter.cc \
util/slice.cc \
util/sst_file_manager_impl.cc \
util/status.cc \
util/status_message.cc \
util/string_util.cc \
util/sync_point.cc \
util/sync_point_impl.cc \
util/thread_local.cc \
util/threadpool_imp.cc \
util/transaction_test_util.cc \
util/xxhash.cc \
utilities/backupable/backupable_db.cc \
utilities/blob_db/blob_compaction_filter.cc \
utilities/blob_db/blob_db.cc \
utilities/blob_db/blob_db_impl.cc \
utilities/blob_db/blob_file.cc \
utilities/blob_db/blob_log_format.cc \
utilities/blob_db/blob_log_reader.cc \
utilities/blob_db/blob_log_writer.cc \
utilities/blob_db/ttl_extractor.cc \
utilities/cassandra/cassandra_compaction_filter.cc \
utilities/cassandra/format.cc \
utilities/cassandra/merge_operator.cc \
utilities/checkpoint/checkpoint_impl.cc \
utilities/compaction_filters/remove_emptyvalue_compactionfilter.cc \
utilities/convenience/info_log_finder.cc \
utilities/date_tiered/date_tiered_db_impl.cc \
utilities/debug.cc \
utilities/document/document_db.cc \
utilities/document/json_document.cc \
utilities/document/json_document_builder.cc \
utilities/env_mirror.cc \
utilities/env_timed.cc \
utilities/geodb/geodb_impl.cc \
utilities/leveldb_options/leveldb_options.cc \
utilities/lua/rocks_lua_compaction_filter.cc \
utilities/memory/memory_util.cc \
utilities/merge_operators/max.cc \
utilities/merge_operators/put.cc \
utilities/merge_operators/string_append/stringappend.cc \
utilities/merge_operators/string_append/stringappend2.cc \
utilities/merge_operators/uint64add.cc \
utilities/merge_operators/bytesxor.cc \
utilities/option_change_migration/option_change_migration.cc \
utilities/options/options_util.cc \
utilities/persistent_cache/block_cache_tier.cc \
utilities/persistent_cache/block_cache_tier_file.cc \
utilities/persistent_cache/block_cache_tier_metadata.cc \
utilities/persistent_cache/persistent_cache_tier.cc \
utilities/persistent_cache/volatile_tier_impl.cc \
utilities/redis/redis_lists.cc \
utilities/simulator_cache/sim_cache.cc \
utilities/spatialdb/spatial_db.cc \
utilities/table_properties_collectors/compact_on_deletion_collector.cc \
utilities/transactions/optimistic_transaction.cc \
utilities/transactions/optimistic_transaction_db_impl.cc \
utilities/transactions/pessimistic_transaction.cc \
utilities/transactions/pessimistic_transaction_db.cc \
utilities/transactions/snapshot_checker.cc \
utilities/transactions/transaction_base.cc \
utilities/transactions/transaction_db_mutex_impl.cc \
utilities/transactions/transaction_lock_mgr.cc \
utilities/transactions/transaction_util.cc \
utilities/transactions/write_prepared_txn.cc \
utilities/transactions/write_prepared_txn_db.cc \
utilities/transactions/write_unprepared_txn.cc \
utilities/transactions/write_unprepared_txn_db.cc \
utilities/ttl/db_ttl_impl.cc \
utilities/write_batch_with_index/write_batch_with_index.cc \
utilities/write_batch_with_index/write_batch_with_index_internal.cc \
ifeq (,$(shell $(CXX) -fsyntax-only -maltivec -xc /dev/null 2>&1))
LIB_SOURCES_ASM =\
util/crc32c_ppc_asm.S
LIB_SOURCES_C = \
util/crc32c_ppc.c
else
LIB_SOURCES_ASM =
LIB_SOURCES_C =
endif
TOOL_LIB_SOURCES = \
tools/ldb_cmd.cc \
tools/ldb_tool.cc \
tools/sst_dump_tool.cc \
utilities/blob_db/blob_dump_tool.cc \
MOCK_LIB_SOURCES = \
table/mock_table.cc \
util/fault_injection_test_env.cc
BENCH_LIB_SOURCES = \
tools/db_bench_tool.cc \
EXP_LIB_SOURCES = \
utilities/col_buf_decoder.cc \
utilities/col_buf_encoder.cc \
utilities/column_aware_encoding_util.cc
TEST_LIB_SOURCES = \
db/db_test_util.cc \
util/testharness.cc \
util/testutil.cc \
utilities/cassandra/test_utils.cc \
MAIN_SOURCES = \
cache/cache_bench.cc \
cache/cache_test.cc \
db/column_family_test.cc \
db/compact_files_test.cc \
db/compaction_iterator_test.cc \
db/compaction_job_stats_test.cc \
db/compaction_job_test.cc \
db/compaction_picker_test.cc \
db/comparator_db_test.cc \
db/corruption_test.cc \
db/cuckoo_table_db_test.cc \
db/db_basic_test.cc \
db/db_blob_index_test.cc \
db/db_block_cache_test.cc \
db/db_bloom_filter_test.cc \
db/db_compaction_filter_test.cc \
db/db_compaction_test.cc \
db/db_dynamic_level_test.cc \
db/db_encryption_test.cc \
db/db_flush_test.cc \
db/db_inplace_update_test.cc \
db/db_io_failure_test.cc \
db/db_iter_test.cc \
db/db_iter_stress_test.cc \
db/db_iterator_test.cc \
db/db_log_iter_test.cc \
db/db_memtable_test.cc \
db/db_merge_operator_test.cc \
db/db_options_test.cc \
db/db_properties_test.cc \
db/db_range_del_test.cc \
db/db_sst_test.cc \
db/db_statistics_test.cc \
db/db_table_properties_test.cc \
db/db_tailing_iter_test.cc \
db/db_test.cc \
db/db_test2.cc \
db/db_universal_compaction_test.cc \
db/db_wal_test.cc \
db/db_write_test.cc \
db/dbformat_test.cc \
db/deletefile_test.cc \
db/env_timed_test.cc \
db/external_sst_file_basic_test.cc \
db/external_sst_file_test.cc \
db/fault_injection_test.cc \
db/file_indexer_test.cc \
db/file_reader_writer_test.cc \
db/filename_test.cc \
db/flush_job_test.cc \
db/hash_table_test.cc \
db/hash_test.cc \
db/heap_test.cc \
db/listener_test.cc \
db/log_test.cc \
db/lru_cache_test.cc \
db/manual_compaction_test.cc \
db/memtable_list_test.cc \
db/merge_helper_test.cc \
db/merge_test.cc \
db/obsolete_files_test.cc \
db/options_settable_test.cc \
db/options_file_test.cc \
db/partitioned_filter_block_test.cc \
db/perf_context_test.cc \
db/persistent_cache_test.cc \
db/plain_table_db_test.cc \
db/prefix_test.cc \
db/redis_test.cc \
db/repair_test.cc \
db/range_del_aggregator_test.cc \
db/table_properties_collector_test.cc \
db/util_merge_operators_test.cc \
db/version_builder_test.cc \
db/version_edit_test.cc \
db/version_set_test.cc \
db/wal_manager_test.cc \
db/write_batch_test.cc \
db/write_callback_test.cc \
db/write_controller_test.cc \
env/env_basic_test.cc \
env/env_test.cc \
env/mock_env_test.cc \
memtable/inlineskiplist_test.cc \
memtable/memtablerep_bench.cc \
memtable/skiplist_test.cc \
memtable/write_buffer_manager_test.cc \
monitoring/histogram_test.cc \
monitoring/iostats_context_test.cc \
monitoring/statistics_test.cc \
options/options_test.cc \
table/block_based_filter_block_test.cc \
table/block_test.cc \
table/cleanable_test.cc \
table/cuckoo_table_builder_test.cc \
table/cuckoo_table_reader_test.cc \
table/full_filter_block_test.cc \
table/merger_test.cc \
table/table_reader_bench.cc \
table/table_test.cc \
third-party/gtest-1.7.0/fused-src/gtest/gtest-all.cc \
tools/db_bench.cc \
tools/db_bench_tool_test.cc \
tools/db_sanity_test.cc \
tools/ldb_cmd_test.cc \
tools/reduce_levels_test.cc \
tools/sst_dump_test.cc \
util/arena_test.cc \
util/auto_roll_logger_test.cc \
util/autovector_test.cc \
util/bloom_test.cc \
util/coding_test.cc \
util/crc32c_test.cc \
util/dynamic_bloom_test.cc \
util/event_logger_test.cc \
util/filelock_test.cc \
util/log_write_bench.cc \
util/rate_limiter_test.cc \
util/slice_transform_test.cc \
util/timer_queue_test.cc \
util/thread_list_test.cc \
util/thread_local_test.cc \
utilities/backupable/backupable_db_test.cc \
utilities/blob_db/blob_db_test.cc \
utilities/cassandra/cassandra_format_test.cc \
utilities/cassandra/cassandra_functional_test.cc \
utilities/cassandra/cassandra_row_merge_test.cc \
utilities/cassandra/cassandra_serialize_test.cc \
utilities/checkpoint/checkpoint_test.cc \
utilities/column_aware_encoding_exp.cc \
utilities/column_aware_encoding_test.cc \
utilities/date_tiered/date_tiered_test.cc \
utilities/document/document_db_test.cc \
utilities/document/json_document_test.cc \
utilities/geodb/geodb_test.cc \
utilities/lua/rocks_lua_test.cc \
utilities/memory/memory_test.cc \
utilities/merge_operators/string_append/stringappend_test.cc \
utilities/object_registry_test.cc \
utilities/option_change_migration/option_change_migration_test.cc \
utilities/options/options_util_test.cc \
utilities/redis/redis_lists_test.cc \
utilities/simulator_cache/sim_cache_test.cc \
utilities/spatialdb/spatial_db_test.cc \
utilities/table_properties_collectors/compact_on_deletion_collector_test.cc \
utilities/transactions/optimistic_transaction_test.cc \
utilities/transactions/transaction_test.cc \
utilities/transactions/write_prepared_transaction_test.cc \
utilities/transactions/write_unprepared_transaction_test.cc \
utilities/ttl/ttl_test.cc \
utilities/write_batch_with_index/write_batch_with_index_test.cc \
JNI_NATIVE_SOURCES = \
java/rocksjni/backupenginejni.cc \
java/rocksjni/backupablejni.cc \
java/rocksjni/checkpoint.cc \
java/rocksjni/clock_cache.cc \
java/rocksjni/columnfamilyhandle.cc \
java/rocksjni/compaction_filter.cc \
java/rocksjni/compaction_filter_factory.cc \
java/rocksjni/compaction_filter_factory_jnicallback.cc \
java/rocksjni/compaction_options_fifo.cc \
java/rocksjni/compaction_options_universal.cc \
java/rocksjni/comparator.cc \
java/rocksjni/comparatorjnicallback.cc \
java/rocksjni/compression_options.cc \
java/rocksjni/env.cc \
java/rocksjni/env_options.cc \
java/rocksjni/ingest_external_file_options.cc \
java/rocksjni/filter.cc \
java/rocksjni/iterator.cc \
java/rocksjni/jnicallback.cc \
java/rocksjni/loggerjnicallback.cc \
java/rocksjni/lru_cache.cc \
java/rocksjni/memtablejni.cc \
java/rocksjni/merge_operator.cc \
java/rocksjni/native_comparator_wrapper_test.cc \
java/rocksjni/optimistic_transaction_db.cc \
java/rocksjni/optimistic_transaction_options.cc \
java/rocksjni/options.cc \
java/rocksjni/options_util.cc \
java/rocksjni/ratelimiterjni.cc \
java/rocksjni/remove_emptyvalue_compactionfilterjni.cc \
java/rocksjni/cassandra_compactionfilterjni.cc \
java/rocksjni/cassandra_value_operator.cc \
java/rocksjni/restorejni.cc \
java/rocksjni/rocks_callback_object.cc \
java/rocksjni/rocksjni.cc \
java/rocksjni/rocksdb_exception_test.cc \
java/rocksjni/slice.cc \
java/rocksjni/snapshot.cc \
java/rocksjni/sst_file_manager.cc \
java/rocksjni/sst_file_writerjni.cc \
java/rocksjni/statistics.cc \
java/rocksjni/statisticsjni.cc \
java/rocksjni/table.cc \
java/rocksjni/transaction.cc \
java/rocksjni/transaction_db.cc \
java/rocksjni/transaction_options.cc \
java/rocksjni/transaction_db_options.cc \
java/rocksjni/transaction_log.cc \
java/rocksjni/transaction_notifier.cc \
java/rocksjni/transaction_notifier_jnicallback.cc \
java/rocksjni/ttl.cc \
java/rocksjni/write_batch.cc \
java/rocksjni/writebatchhandlerjnicallback.cc \
java/rocksjni/write_batch_test.cc \
java/rocksjni/write_batch_with_index.cc
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